Audio systems, such as speech recognition or other audio systems are susceptible to interruptions or interference. For example, some speech recognition systems require a close talk microphone to reduce interfering noise as well as a manual input to initiate speech recognition.
In such systems, the user must manually start operation. The user must also repetitively stop recognition each time the user is interrupted or whenever there is excessive background noise. Following interruption, the user must restart operation or speech recognition. This type of manual control of speech recognition intervals can be burdensome if the user faces multiple interruptions or if the user is in a noisy environment. Additionally interfering or background noise can degrade speech recognition quality since the system may process the background noise instead of the user's speech.
Some microphone arrays are used in speech recognition and can provide direction-sensitive noise suppression to limit noise interference. Such microphone arrays can estimate the direction from which sound is arriving and focus audio detection on the user by focusing on the loudest sound. However, in many instances, the loudest sound may not be from the user and in such circumstances, the microphone array is mis-focused. The present invention addresses one or more of these and/or other problems and has application for speech recognition systems and other audio systems.